[DOC OCP] Remove “The JVM’s overall memory usage will be approximately 4 × the maximum heap”

• Remove “The JVM’s overall memory usage will be approximately 4 × the maximum heap”[1].
  • This statement is no longer correct.
  • Actually, I think that "Use a memory request that is at least 4.5 × the -Xmx", which is described later in the same document, is more practical than the problematic statement, and as a result, it achieves its original purpose.

[1] Using AMQ Streams on OpenShift > jvmOptions
    https://access.redhat.com/documentation/en-us/red_hat_amq/2021.q3/html/using_amq_streams_on_openshift/api_reference-str#con-common-configuration-jvm-reference
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The JVM’s overall memory usage will be approximately 4 × the maximum heap, as configured by -Xmx.
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Use a memory request that is at least 4.5 × the -Xmx
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